Difference in "need to specify version" between jsr and deno.land

[Xernisfy]

Hi Deno community,

since the launch of JSR 🎉 I've noticed, that you don't have to (or even should?) specify a version when importing a dependency.
You just import { dirname } from 'jsr:@std/path'; and it will resolve to the latest version by default.
When compared to deno.land it's recommended that you specify a version.
Otherwise you get squiggly lines on the import:

The resolution works completely fine either way:

Service	Specific version	No version
jsr	works ✔️	works ✔️
deno.land	works ✔️	works ✔️

I quite like not having to specify a version, as it checks for the newest dependencies on each run (if you don't use a lockfile).

But why is there a difference in how versions are expected?
Is the warning for "Implicitly using latest version..." necessary?

Kind regards

[marvinhagemeister]

You can skip adding a version if:

• you're writing a simple app or one of script
• you are prototyping something
• don't care if your app keeps working in the future (because it's a prototype etc)

You should always use a version or version constraint together with a lockfile if:

• more than one dev work on the code
• the app should keep working in the future
• you don't want to spent time debugging why the app works on machine A, but not on machine B (this typically happens because of different dependency version installed on the users machine. A lockfile prevents this)

We strongly recommend going with the versioned approach for any serious project. Only consider going without versions if it's a short lived prototype that only a single developer hacks on.

[karfau]

Maybe worth mentioning in that context (because it's hard to find in the docs),
that it's possible to specify a version AND a path into the package, e.g.

export { describe, it } from "jsr:@std/[email protected]/bdd";